/*
 * Copyright (C) 2012 The Guava Authors
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.google.common.collect.testing.google;

import com.google.common.annotations.GwtIncompatible;
import com.google.common.collect.BiMap;
import com.google.common.collect.testing.AbstractTester;
import com.google.common.collect.testing.FeatureSpecificTestSuiteBuilder;
import com.google.common.collect.testing.MapTestSuiteBuilder;
import com.google.common.collect.testing.OneSizeTestContainerGenerator;
import com.google.common.collect.testing.PerCollectionSizeTestSuiteBuilder;
import com.google.common.collect.testing.SetTestSuiteBuilder;
import com.google.common.collect.testing.features.CollectionFeature;
import com.google.common.collect.testing.features.Feature;
import com.google.common.collect.testing.features.MapFeature;
import com.google.common.collect.testing.google.DerivedGoogleCollectionGenerators.BiMapValueSetGenerator;
import com.google.common.collect.testing.google.DerivedGoogleCollectionGenerators.InverseBiMapGenerator;
import com.google.common.collect.testing.google.DerivedGoogleCollectionGenerators.MapGenerator;
import com.google.common.collect.testing.testers.SetCreationTester;

import java.util.ArrayList;
import java.util.Collections;
import java.util.HashSet;
import java.util.List;
import java.util.Map.Entry;
import java.util.Set;

import junit.framework.TestSuite;

/**
 * Creates, based on your criteria, a JUnit test suite that exhaustively tests a {@code BiMap}
 * implementation.
 *
 * @author Louis Wasserman
 */
@GwtIncompatible
public class BiMapTestSuiteBuilder<K, V>
        extends PerCollectionSizeTestSuiteBuilder<
        BiMapTestSuiteBuilder<K, V>, TestBiMapGenerator<K, V>, BiMap<K, V>, Entry<K, V>>
{
    public static <K, V> BiMapTestSuiteBuilder<K, V> using(TestBiMapGenerator<K, V> generator)
    {
        return new BiMapTestSuiteBuilder<K, V>().usingGenerator(generator);
    }

    @Override
    protected List<Class<? extends AbstractTester>> getTesters()
    {
        List<Class<? extends AbstractTester>> testers = new ArrayList<>();
        testers.add(BiMapEntrySetTester.class);
        testers.add(BiMapPutTester.class);
        testers.add(BiMapInverseTester.class);
        testers.add(BiMapRemoveTester.class);
        testers.add(BiMapClearTester.class);
        return testers;
    }

    enum NoRecurse implements Feature<Void>
    {
        INVERSE;

        @Override
        public Set<Feature<? super Void>> getImpliedFeatures()
        {
            return Collections.emptySet();
        }
    }

    @Override
    protected List<TestSuite> createDerivedSuites(
            FeatureSpecificTestSuiteBuilder<
                    ?, ? extends OneSizeTestContainerGenerator<BiMap<K, V>, Entry<K, V>>>
                    parentBuilder)
    {
        List<TestSuite> derived = super.createDerivedSuites(parentBuilder);
        // TODO(cpovirk): consider using this approach (derived suites instead of extension) in
        // ListTestSuiteBuilder, etc.?
        derived.add(
                MapTestSuiteBuilder.using(new MapGenerator<K, V>(parentBuilder.getSubjectGenerator()))
                        .withFeatures(parentBuilder.getFeatures())
                        .named(parentBuilder.getName() + " [Map]")
                        .suppressing(parentBuilder.getSuppressedTests())
                        .suppressing(SetCreationTester.class.getMethods())
                        // BiMap.entrySet() duplicate-handling behavior is too confusing for SetCreationTester
                        .withSetUp(parentBuilder.getSetUp())
                        .withTearDown(parentBuilder.getTearDown())
                        .createTestSuite());
        /*
         * TODO(cpovirk): the Map tests duplicate most of this effort by using a
         * CollectionTestSuiteBuilder on values(). It would be nice to avoid that
         */
        derived.add(
                SetTestSuiteBuilder.using(
                                new BiMapValueSetGenerator<K, V>(parentBuilder.getSubjectGenerator()))
                        .withFeatures(computeValuesSetFeatures(parentBuilder.getFeatures()))
                        .named(parentBuilder.getName() + " values [Set]")
                        .suppressing(parentBuilder.getSuppressedTests())
                        .suppressing(SetCreationTester.class.getMethods())
                        // BiMap.values() duplicate-handling behavior is too confusing for SetCreationTester
                        .withSetUp(parentBuilder.getSetUp())
                        .withTearDown(parentBuilder.getTearDown())
                        .createTestSuite());
        if (!parentBuilder.getFeatures().contains(NoRecurse.INVERSE))
        {
            derived.add(
                    BiMapTestSuiteBuilder.using(
                                    new InverseBiMapGenerator<K, V>(parentBuilder.getSubjectGenerator()))
                            .withFeatures(computeInverseFeatures(parentBuilder.getFeatures()))
                            .named(parentBuilder.getName() + " inverse")
                            .suppressing(parentBuilder.getSuppressedTests())
                            .withSetUp(parentBuilder.getSetUp())
                            .withTearDown(parentBuilder.getTearDown())
                            .createTestSuite());
        }

        return derived;
    }

    private static Set<Feature<?>> computeInverseFeatures(Set<Feature<?>> mapFeatures)
    {
        Set<Feature<?>> inverseFeatures = new HashSet<>(mapFeatures);

        boolean nullKeys = inverseFeatures.remove(MapFeature.ALLOWS_NULL_KEYS);
        boolean nullValues = inverseFeatures.remove(MapFeature.ALLOWS_NULL_VALUES);

        if (nullKeys)
        {
            inverseFeatures.add(MapFeature.ALLOWS_NULL_VALUES);
        }
        if (nullValues)
        {
            inverseFeatures.add(MapFeature.ALLOWS_NULL_KEYS);
        }

        inverseFeatures.add(NoRecurse.INVERSE);
        inverseFeatures.remove(CollectionFeature.KNOWN_ORDER);
        inverseFeatures.add(MapFeature.REJECTS_DUPLICATES_AT_CREATION);

        return inverseFeatures;
    }

    // TODO(lowasser): can we eliminate the duplication from MapTestSuiteBuilder here?

    private static Set<Feature<?>> computeValuesSetFeatures(Set<Feature<?>> mapFeatures)
    {
        Set<Feature<?>> valuesCollectionFeatures = computeCommonDerivedCollectionFeatures(mapFeatures);
        valuesCollectionFeatures.add(CollectionFeature.ALLOWS_NULL_QUERIES);

        if (mapFeatures.contains(MapFeature.ALLOWS_NULL_VALUES))
        {
            valuesCollectionFeatures.add(CollectionFeature.ALLOWS_NULL_VALUES);
        }

        valuesCollectionFeatures.add(CollectionFeature.REJECTS_DUPLICATES_AT_CREATION);

        return valuesCollectionFeatures;
    }

    private static Set<Feature<?>> computeCommonDerivedCollectionFeatures(
            Set<Feature<?>> mapFeatures)
    {
        return MapTestSuiteBuilder.computeCommonDerivedCollectionFeatures(mapFeatures);
    }
}
